XML 42 R30.htm IDEA: XBRL DOCUMENT
v3.8.0.1

Revenue from Contracts with Customers - Disaggregation of Revenue (Details) - USD ($) $ in Thousands | 3 Months Ended
--- | ---
Mar. 31, 2018 | Mar. 31, 2017
Segment Reporting Information [Line Items] |  |
Oil production revenue | $ 261,060 | $ 167,624
Gas production revenue | 79,109 | 101,151
NGL production revenue | 42,717 | 64,423
Total oil, gas, and NGL production revenue | 382,886 | 333,198
Permian |  |
Segment Reporting Information [Line Items] |  |
Oil production revenue | 205,794 | 81,499
Gas production revenue | 24,876 | 11,309
NGL production revenue | 124 | 147
Total oil, gas, and NGL production revenue | 230,794 | 92,955
South Texas & Gulf Coast |  |
Segment Reporting Information [Line Items] |  |
Oil production revenue | 19,583 | 38,864
Gas production revenue | 52,733 | 88,201
NGL production revenue | 41,770 | 63,357
Total oil, gas, and NGL production revenue | 114,086 | 190,422
Rocky Mountain |  |
Segment Reporting Information [Line Items] |  |
Oil production revenue | 35,683 | 47,261
Gas production revenue | 1,500 | 1,641
NGL production revenue | 823 | 919
Total oil, gas, and NGL production revenue | $ 38,006 | $ 49,821
Sales Revenue, Net | Geographic Concentration Risk |  |
Segment Reporting Information [Line Items] |  |
Relative percentage | 100.00% | 100.00%
Sales Revenue, Net | Geographic Concentration Risk | Permian |  |
Segment Reporting Information [Line Items] |  |
Relative percentage | 60.00% | 28.00%
Sales Revenue, Net | Geographic Concentration Risk | South Texas & Gulf Coast |  |
Segment Reporting Information [Line Items] |  |
Relative percentage | 30.00% | 57.00%
Sales Revenue, Net | Geographic Concentration Risk | Rocky Mountain |  |
Segment Reporting Information [Line Items] |  |
Relative percentage | 10.00% | 15.00%

X
- Definition Oil Revenue + References No definition available. + Details
Name: | sm_OilRevenue
Namespace Prefix: | sm_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 275 -SubTopic 10 -Section 50 -Paragraph 18 -URI http://asc.fasb.org/extlink&oid=84177426&loc=d3e6351-108592 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 20 -URI http://asc.fasb.org/extlink&oid=77997519&loc=d3e13531-108611 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 275 -SubTopic 10 -Section 50 -Paragraph 20 -URI http://asc.fasb.org/extlink&oid=84177426&loc=d3e6404-108592 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 21 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=77997519&loc=d3e13537-108611 + Details
Name: | us-gaap_ConcentrationRiskPercentage1
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Revenue from natural gas production during the reporting period. Natural gas consists largely of the hydrocarbon methane, and is found in underground formations either by itself or with crude oil. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 225 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.1) -URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 235 -Section 50 -Paragraph 23 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=68064819&loc=d3e62136-109447 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 235 -Section 50 -Paragraph 24 -URI http://asc.fasb.org/extlink&oid=68064819&loc=d3e62246-109447 + Details
Name: | us-gaap_NaturalGasProductionRevenue
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Revenue from sale of residue oil and condensate, which normally exists in the reservoir as gas but condenses out as a liquid during production. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 225 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.1) -URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 235 -Section 50 -Paragraph 23 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=68064819&loc=d3e62136-109447 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 235 -Section 50 -Paragraph 24 -URI http://asc.fasb.org/extlink&oid=68064819&loc=d3e62246-109447 + Details
Name: | us-gaap_OilAndCondensateRevenue
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Revenue from the sale of oil and gas during the period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 235 -Section 50 -Paragraph 24 -URI http://asc.fasb.org/extlink&oid=68064819&loc=d3e62246-109447 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 225 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.1) -URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 235 -Section 50 -Paragraph 23 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=68064819&loc=d3e62136-109447 + Details
Name: | us-gaap_OilAndGasSalesRevenue
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
Name: | us-gaap_SegmentReportingInformationLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_StatementGeographicalAxis=sm_PermianRegionMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_StatementGeographicalAxis=sm_SouthTexasGulfCoastMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_StatementGeographicalAxis=sm_RockyMountainRegionMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_ConcentrationRiskByBenchmarkAxis=us-gaap_SalesRevenueNetMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_ConcentrationRiskByTypeAxis=us-gaap_GeographicConcentrationRiskMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |